1)nominee is only trustee for legal heirs

2) since your grand father died intestate on his demise your father as nominee would entitled to FD proceeds

3) bank would insist on NOC from other legal heirs . also insist on indemnity bond

4) on demise of your father your mother and children would be entitled only to one third share in FD

5) apply for and obtain succession certifcate from court in name of all the legal heirs

7)enclose certifed copy of father death certtifcate

8) you would get succession certifcate in 6 months time

nominee is dead

2) bank would insist on succession certifcate ,

3) in alternative insist on NOC from legal heirs

yes, you can get fresh death certificate because there is no bar that more than one certificate cannot be issued. death certificate does not give any right, it is a document unlike of valuable security u/s 30 ipc so it cannot be said that you get duplicate copy of a valuable document.

Your grandfather's amount lying in FD shall be distributed to the legal heirs/successor equally.

The nominee is not a legal heir hence his legal heirs are not entitled to the money of the depositor.

The FD amount can be settled in favor of all legal heirs of your grandfather, out of which one share shall be allotted to your father for the benefits of his legal heirs.

You can get a copy of the original death extract from the registrar of births and deaths within your jurisdiction.

Bank should not insist for succession certificate,NOC,or any other documents in case there is nomination.

Since the nominee is no more alive then the bank may insist on the succession certificate or at least an indemnity bond if the claim amount is low.